Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Scale traditional

As the science, technology, and an of vollammciric instrumentation and data reduction methods have developed, so too have the time and spatial regimes of voltammetry decreased in scale. Traditionally, voltam-metric measurements were made at dc and relatively low frequency. As a result, only relatively slow electron-transfer processes could he explored using these methods. [Pg.745]

The resistance to deformation at the surface can be quantified at the micrometer and nanometer scale. At the micrometer scale, traditional hardness measurements are conducted on a polymer system using a handheld durometer, whereby the penetration tip is varied to properly quantify the Shore hardness. At the nanometer scale, measurements of modulus and depth of penetration are quantified using quasi-static nanoindentation. Increases in stiffiiess at the surface of an American football helmet outer shell material exposed to accelerated weathering (Krzeminski et al., 2014c) and repetitive linear impacts (Krzeminski et al., 2014b) have been quantified using quasi-static nanoindentation. However, Shore A hardness measurements were reported to be overly forceful to quantify shifts in surface mechanical properties of injection-molded American football helmet outer shell materials (Krzeminski et al., 2014b,c). [Pg.231]

Process development is a long and expensive process. Time is often the decisive factor whether a new process or product will be profitable or not. Profits of new products are often the highest when they are introduced into the market and along with competition the prizes will decrease and reduce the profitability. The most time consuming stage is to make experiments in various scales. Traditionally process development is done in consecutive steps and disciplines. If the experiments in the different scales could be performed simultaneously, or at least overlapping each other, the development would be faster. This will also mean a quicker return of investment. [Pg.761]

The goals of microscopic theories of chemical rate processes are to define the range of validity of the macroscopic law, to provide microscopic expressions for the rate coefficients and to extend the kinetic description to smaller distance and time scales. Traditional approaches model the isomerization reaction by motion of a particle of mass m across a potential barrier in a thermal bath of temperature T. Transition state theory (TST) [2] assumes an equilibrium distribution at the barrier top the rate is given by the equilibrium one-way flux across the barrier. The rate thus obtained has the form ... [Pg.298]

Analytical chemists work to improve the ability of all chemists to make meaningful measurements. Chemists working in medicinal chemistry, clinical chemistry, forensic chemistry, and environmental chemistry, as well as the more traditional areas of chemistry, need better tools for analyzing materials. The need to work with smaller quantities of material, with more complex materials, with processes occurring on shorter time scales, and with species present at lower concentrations challenges analytical... [Pg.9]

Acetylene traditionally has been made from coal (coke) via the calcium carbide process. However, laboratory and bench-scale experiments have demonstrated the technical feasibiUty of producing the acetylene by the direct pyrolysis of coal. Researchers in Great Britain (24,28), India (25), and Japan (27) reported appreciable yields of acetylene from the pyrolysis of coal in a hydrogen-enhanced argon plasma. In subsequent work (29), it was shown that the yields could be dramatically increased through the use of a pure hydrogen plasma. [Pg.391]

Flame Resistance. Traditionally, small-scale laboratory flammabiUty tests have been used to initially characterize foams (38). However, these do not reflect the performance of such materials in bulk form. Fire characteristics of thermal insulations for building appHcations are generally reported in the form of quaHtative or semiquantitative results from ASTM E84 or similar tunnel tests (39). Similar larger scale tests are used for aircraft and marine appHcations. [Pg.336]

Conventional, incoherent light sources suitable for industrial-scale photochemistry and the reactors exploiting them have been reviewed in depth (2). Subsequent improvements in traditional light sources have been incremental. [Pg.388]

Traditionally, this process has been utilized primarily for simple soap bars because it tends to be time-consuming and thus somewhat limited for large-scale bar production. However, advances have been reported in automating this approach (14). Furthermore, the process requires fluid cmtcher compositions for flow into the molds. This typically requires the formulation to contain either a high level of solvents, including water, glycerol, and alcohol, and be at elevated temperatures (>80° C) when poured into the frames. Despite these limitations, it has proven to be the preferred route to producing certain specialty products, for example, transparent bars. [Pg.156]


See other pages where Scale traditional is mentioned: [Pg.113]    [Pg.1]    [Pg.1435]    [Pg.287]    [Pg.617]    [Pg.1009]    [Pg.194]    [Pg.307]    [Pg.110]    [Pg.526]    [Pg.317]    [Pg.110]    [Pg.30]    [Pg.248]    [Pg.388]    [Pg.399]    [Pg.113]    [Pg.1]    [Pg.1435]    [Pg.287]    [Pg.617]    [Pg.1009]    [Pg.194]    [Pg.307]    [Pg.110]    [Pg.526]    [Pg.317]    [Pg.110]    [Pg.30]    [Pg.248]    [Pg.388]    [Pg.399]    [Pg.316]    [Pg.246]    [Pg.333]    [Pg.435]    [Pg.595]    [Pg.4]    [Pg.260]    [Pg.87]    [Pg.178]    [Pg.180]    [Pg.441]    [Pg.455]    [Pg.510]    [Pg.515]    [Pg.298]    [Pg.455]    [Pg.343]    [Pg.237]    [Pg.474]    [Pg.190]    [Pg.264]    [Pg.97]    [Pg.284]    [Pg.1365]    [Pg.1634]   
See also in sourсe #XX -- [ Pg.15 , Pg.17 , Pg.31 ]




SEARCH



© 2024 chempedia.info